The 3 proteins actin, tropomyosin, & troponin are part of which myofilaments

A. Thick
B. Thin

B. Thin

Predominant protein; the backbone of each thin filament is formed by two strands of actin that coil around each other (looks like a twisted double strand of pearls); the actin molecule contains a myosin-binding site for a myosin molecule

A. TropmyosinB. Actin
C. Troponin

B. Actin

(this multiple choice question has been scrambled)

Tropomyosin spirals around the actin backbone; in the absence of calcium, tropomyosin blocks myosin from binding to actin.

A. ActinB. Tropmyosin
C. Troponin

B. Tropomyosin

(this multiple choice question has been scrambled)

Complex of three protein molecules; one
binds to actin, another binds to tropomyosin, & the third binds to calcium ions; when calcium is present, troponin moves tropomyosin out of the way so that myosin can bind to actin.

A. Troponin
B. Actin
C. Tropmyosin

A. Troponin

(this multiple choice question has been scrambled)

What is the smallest contractile unit of a muscle cell

Sarcomeres

The number of myofibers per motor unit is higher in muscles that exert fine control and higher in muscles whose movements are less precise.

A. True
B. False

False

Which of these structures is not part of a neuromuscular junction?

A. Synaptic end bulb
B. Motor end plateC. all are part of junction
D. Synaptic vesicles
E. acetylcholine